1. Field of the Invention
The present invention relates to a camera system in which data are exchanged through electrical contacts between a camera body and an interchangeable lens or an intermediate accessory.
2. Related Background Art
There are already proposed various systems for transmitting serial data, for enabling a camera body such as of a single lens reflex camera to receive various information from a lens. For example the U.S. Pat. No. 4,572,638 discloses a system including an intermediate accessory such as a teleconversion lens to be inserted between a camera body and an interchangeable lens, wherein said system contains a terminal for initiating data transmission to the camera body, a clock pulse terminal and a data transmitting terminal. In case said intermediate accessory is employed, the lens data are transmitted to the camera body through an operation circuit of the intermediate accessory. Such system with intermediate accessory not only requires time for the camera body to receive the data but also complicates the structure of said intermediate accessory.